Written by Jina Bae, Specsavers Optometrist
Some Glaucoma NZ members recognise that intraocular pressure is important, but admit that they aren’t sure why. We asked Specsavers Optometrist, Jina Bae, to explain what intraocular pressure (IOP) is and what it has to do with glaucoma.
What is intraocular pressure (IOP)?
Intraocular pressure (IOP) is simply the pressure inside your eye. All eyes produce and drain fluid at different rates, leaving the eye with a varying rate of pressure. Normal IOP falls between 10-21 mmHg, but this can vary from person to person.
Why is IOP linked to glaucoma?
Glaucoma is an eye disease that damages the optic nerve, which is responsible for sending visual information to your brain. High eye pressure is the biggest risk factor for glaucoma, though some people can still develop glaucoma with normal IOP—this is called normal-tension glaucoma.
Why is controlling IOP so important?
Lowering eye pressure can reduce the risk of glaucoma progression. While not everyone with high IOP develops glaucoma, it’s still the most important modifiable risk factor. That’s why regular eye exams are crucial—to catch and manage high IOP to reduce the risk of preventable vision loss.
Does everyone with high IOP get glaucoma?
Not always. Some people can have high eye pressure but never develop glaucoma (this is called ocular hypertension). On the other hand, some people do get glaucoma even with normal IOP. But regardless of the numbers, keeping your IOP in check is key to protecting your vision.
How is IOP controlled?
To control your IOP, your specialist may recommend one or more treatments to reduce fluid production or improve fluid drainage:
- Eye drops
- Oral medications
- Laser treatments
- Surgery
Can you feel the difference if you have a high IOP?
If you have high IOP, you most likely would never know until you have an eye test and it is measured. If you waited until you experienced symptoms relevant to high IOP or glaucoma such as blurred vision, halos around lights, eye paid or nausea, it is likely damage would have already been done to your optic nerve. The best thing to do is to have regular eye tests so that you can ensure your eyes are healthy and anything detected can be managed early and effectively.
The bottom line:
Glaucoma usually has no symptoms until advanced vision loss occurs. That’s why regular eye check-ups at least once every two years or more often if clinically recommended or you experience any changes to vision or eyes are a must. Catching eye conditions like glaucoma early and keeping your intraocular pressure under control are some of the best ways to protect your sight for the long run.
Jina Bae is a dedicated optometrist with a passion for improving eye health awareness. After completing her Bachelor’s degree in Optometry at The University of Auckland in 2022, she gained extensive clinical experience at Specsavers, Dunedin where she has worked for more than two years.
Image credit: istockphoto.com/TefiM